[Analysis of the new WHO guideline to accelerate the progress towards elimination of schistosomiasis in China]

On February 2022, WHO released the evidence-based guideline on control and elimination of human schistosomiasis, with aims to guide the elimination of schistosomiasis as a public health problem in disease-endemic countries by 2030 and promote the interruption of schistosomiasis transmission across the world. Based on the One Health concept, six evidence-based recommendations were proposed in this guideline. This article aims to analyze the feasibility of key aspects of this guideline in Chinese national schistosomiasis control program and illustrate the significance to guide the future actions for Chinese national schistosomiasis control program. Currently, the One Health concept has been embodied in the Chinese national schistosomiasis control program. Based on this new WHO guideline, the following recommendations are proposed for the national schistosomiasis control program of China: (1) improving the systematic framework building, facilitating the agreement of the cross-sectoral consensus, and building a high-level leadership group; (2) optimizing the current human and livestock treatments in the national schistosomiasis control program of China; (3) developing highly sensitive and specific diagnostics and the framework for verifying elimination of schistosomiasis; (4) accelerating the progress towards elimination of schistosomiasis and other parasitic diseases through integrating the national control programs for other parasitic diseases.

[Contribution to global implementation of WHO guideline on control and elimination of human schistosomiasis by learning successful experiences from the national schistosomiasis control program in China]

Schistosomiasis is a parasitic disease that seriously hinders socioeconomic developments and threatens public health security. To achieve the global elimination of schistosomiasis as a public health problem by 2030, WHO released the guideline on control and elimination of human schistosomiasis on February, 2022, with aims to provide evidence-based recommendations for schistosomiasis morbidity control, elimination of schistosomiasis as a public health problem, and ultimate interruption of schistosomiasis transmission in disease-endemic countries. Following concerted efforts for decades, great achievements have been obtained for schistosomiasis control in China where the disease was historically highly prevalent, and the country is moving towards schistosomiasis elimination. This article reviews the successful experiences from the national schistosmiasis control program in China, and summarizes their contributions to the formulation and implementation of the WHO guideline on control and elimination of human schistosomiasis. With the progress of the "Belt and Road" initiative, the world is looking forward to more China's solutions on schistosomiasis control.

[Genes associated with Wolbachia-induced cytoplasmic incompatibility in natural populations of Culex pipiens pallens: a preliminary study]

OBJECTIVE

To investigate the genes involved in Wolbachia-induced cytoplasmic incompatibility among three natural populations of Culex pipiens pallens in eastern China, so as to provide insights into the development of preventive and control measures for mosquito-borne diseases based on Wolbachia.

METHODS

The cytoplasmic incompatibility was tested among three natural populations of C. pipiens pallens collected from Nanjing and Wuxi of Jiangsu Province and Tangkou of Shandong Province using reciprocal crosses. Wolbachia infection was detected in C. pipiens pallens using a PCR assay, and the expression of Wolbachia wsp and WD0513 genes was quantified using a fluorescent quantitative real-time PCR (qPCR) assay.

RESULTS

Bidirectional compatibility was found between the natural populations of C. pipiens pallens collected from Nanjing and Wuxi of Jiangsu Province (t = 0.57 and 0.15, both P values > 0.05), while bidirectional incompatibility was seen between the natural populations of C. pipiens pallens collected from Tangkou of Shandong Province and Wuxi of Jiangsu Province (t = 63.81 and 43.51, both P values < 0.01), and between the natural populations of C. pipiens pallens collected from Nanjing of Jiangsu Province and Tangkou of Shandong Province (t = 39.62 and 43.12, both P values < 0.01). Wolbachia wsp gene was amplified in all three natural populations of C. pipiens pallens, and qPCR assay detected no significant difference in the Wolbachia wsp gene expression among the three natural populations of C. pipiens pallens (F = 2.15, P > 0.05). In addition, there was no significant difference in the WD0513 gene expression between the natural populations of C. pipiens pallens collected from Tangkou of Shandong Province and Nanjing of Jiangsu Province (q = 8.42, P < 0.05) or between the natural populations of C. pipiens pallens collected from Tangkou of Shandong Province and Wuxi of Jiangsu Province (q = 7.84, P < 0.05); however, there was a significant difference detected in the WD0513 gene expression between the natural populations of C. pipiens pallens collected from Nanjing and Wuxi of Jiangsu Province (q = 0.40, P > 0.05).

CONCLUSIONS

Different Wolbachia numbers are detected in natural populations of C. pipiens pallens collected from Nanjing and Wuxi of Jiangsu Province and Tangkou of Shandong Province, and WD0513 gene may be involved in the Wolbachia-induced cytoplasmic incompatibility among three natural populations of C. pipiens pallens.

[Advances in the research on the interaction between human parasites and gut microbiota]

Human parasites may interact with the microbiome parasitizing in human and mammalian intestines. The interplay between intestinal parasites and gut microbiota and its potential impacts have been widely reported; however, some parasites that do not parasitize in intestines may also affect the characteristic of gut microbiota. Hereby, we review the advances in the research on the impacts of parasites inside and outside of human intestines on the gut microbiota.

The condensin component NCAPG2 regulates microtubule-kinetochore attachment through recruitment of Polo-like kinase 1 to kinetochores

The early event of microtubule-kinetochore attachment is a critical stage for precise chromosome segregation. Here we report that NCAPG2, which is a component of the condensin II complex, mediates chromosome segregation through microtubule-kinetochore attachment by recruiting PLK1 to prometaphase kinetochores. NCAPG2 colocalizes with PLK1 at prometaphase kinetochores and directly interacts with the polo-box domain (PBD) of PLK1 via its highly conserved C-terminal region. In both humans and Caenorhabditis elegans, when NCAPG2 is depleted, the attachment of the spindle to the kinetochore is loosened and misoriented. This is caused by the disruption of PLK1 localization to the kinetochore and by the decreased phosphorylation of its kinetochore substrate, BubR1. In addition, the crystal structure of the PBD of PLK1, in complex with the C-terminal region of NCAPG2, (1007)VLS-pT-L(1011), exhibits structural conservation of PBD-phosphopeptides, suggesting that the regulation of NCAPG2 function is phosphorylation-dependent. These findings suggest that NCAPG2 plays an important role in regulating proper chromosome segregation through a functional interaction with PLK1 during mitosis.

Hyperthyroid monkeys: a nonhuman primate model of experimental Graves' disease

Graves' disease (GD) is a common organ-specific autoimmune disease with the prevalence between 0.5 and 2% in women. Several lines of evidence indicate that the shed A-subunit rather than the full-length thyrotropin receptor (TSHR) is the autoantigen that triggers autoimmunity and leads to hyperthyroidism. We have for the first time induced GD in female rhesus monkeys, which exhibit greater similarity to patients with GD than previous rodent models. After final immunization, the monkeys injected with adenovirus expressing the A-subunit of TSHR (A-sub-Ad) showed some characteristics of GD. When compared with controls, all the test monkeys had significantly higher TSHR antibody levels, half of them had increased total thyroxine (T₄) and free T₄, and 50% developed goiter. To better understand the underlying mechanisms, quantitative studies on subpopulations of CD4+T helper cells were carried out. The data indicated that this GD model involved a mixed Th1 and Th2 response. Declined Treg proportions and increased Th17:Treg ratio are also observed. Our rhesus monkey model successfully mimicked GD in humans in many aspects. It would be a useful tool for furthering our understanding of the pathogenesis of GD and would potentially shorten the distance toward the prevention and treatment of this disease in human.

Prolongation of rat intestinal allograft survival by administration of triptolide-modified donor bone marrow-derived dendritic cells

Severe graft rejection remains an important obstacle in intestinal transplantation. In this study, dendritic cells (DCs) isolated from rat bone marrow were cultured for 5 days, and triptolide applied for 3 more days. The recipient rats were pretreated with donor triptolide-modified or not modified DC. Small bowel transplantation was performed to observed survival times. We demonstrated that triptolide markedly inhibited both the expression of CD80 and MHCII expression on DCs. Triptolide-modified DCs stimulated lower proliferative responses among allogeneic T cells, prolonging the survival of intestinal allografts in rats. These results suggested that pretreatment with triptolide-modified DC prolonged the survival of rat small bowel allografts after transplantation.

Prolongation of rat intestinal allograft survival by administration of donor interleukin-12 p35-silenced bone marrow-derived dendritic cells

Severe graft rejection remains an important obstacle in intestinal transplantation. In this study, we demonstrated that intravenous injection of interleukin (IL)-12 p35 siRNA-transfected dendritic cells (DCs) into recipient rats prolonged the survival of intestinal allografts. Serum IL-2 and interferon-gamma levels in the IL-12 p35 siRNA-transfected DCs treatment group were both significantly lower than in control groups at 7 days after transplantation. Further study is required to investigate the operative pathways and to optimize the strategy targeting dendritic cells to induce tolerance to intestinal allografts.

IFN-gamma is associated with risk of Schistosoma japonicum infection in China

Before the start of the schistosomiasis transmission season, 129 villagers resident on a Schistosoma japonicum-endemic island in Poyang Lake, Jiangxi Province, 64 of whom were stool-positive for S. japonicum eggs by the Kato method and 65 negative, were treated with praziquantel. Forty-five days later the 93 subjects who presented for follow-up were all stool-negative. Blood samples were collected from all 93 individuals. S. japonicum soluble worm antigen (SWAP) and soluble egg antigen (SEA) stimulated IL-4, IL-5 and IFN-gamma production in whole-blood cultures were measured by ELISA. All the subjects were interviewed nine times during the subsequent transmission season to estimate the intensity of their contact with potentially infective snail habitats, and the subjects were all re-screened for S. japonicum by the Kato method at the end of the transmission season. Fourteen subjects were found to be infected at that time. There was some indication that the risk of infection might be associated with gender (with females being at higher risk) and with the intensity of water contact, and there was evidence that levels of SEA-induced IFN-gamma production were associated with reduced risk of infection.

Down-regulation of specific antigen-driven cytokine production in a population with endemic Schistosoma japonicum infection

Schistosome antigen-driven cytokine responses and antischistosome antibody levels of residents of a Schistosoma japonicum endemic island in Poyang Lake, Jiangxi Province were studied before and 45 days after treatment with praziquantel. IL-4, IL-5, IL-10 and INF-gamma were all detected in the supernatants of whole-blood cultures after stimulation with schistosome soluble egg antigen (SEA) and soluble worm antigen preparation (SWAP). The percentages of subjects producing detectable amounts of each cytokine assayed were higher in the group who were negative by stool examination at the start of the study than in those who were initially stool positive. After praziquantel treatment the percentages of subjects producing both type I and type II cytokines increased. This suggests that the production of both types of cytokine was down-regulated in the presence of live, egg-laying S. japonicum adult worms but that this was reversible by treatment. In contrast, the antibody studies showed higher levels of SWAP and SEA-specific antibodies (IgE, total IgG, IgG4, IgM) in subjects who were originally stool-positive than in those who were stool-negative. After treatment specific IgE responses were elevated, but total IgG and IgG4 anti-SEA and IgM anti-SWAP antibody levels all fell significantly.

Autologous bone marrow mixed with HLA-haploidentical allogeneic marrow transplantation for treatment of patients with malignant blood diseases

We have previously demonstrated that syngeneic marrow mixed with H-2 haploidentical marrow transplantation could provide not only protection against graft-versus-host disease (GVHD) but also anti-leukemic (GVL) effects in mice. In the present studies, we report clinical observations using autologous marrow mixed with HLA-haploidentical allogeneic marrow transplantation for treatment of patients with malignant blood diseases. Sixteen cases, including 12 with acute leukemia and four with advanced malignant lymphoma, were treated by autologous marrow, which was purged in vitro by hyperthemia (42.5 degrees C for 70 min) following incubation for 5 days with interleukin 2 (IL-2) in liquid culture and mixed with HLA haploidentical marrow cells from their sibling or parent. Acute GVHD was not observed in any patient after transplantation. Hematological rescue in the clinical setting was demonstrated in all cases but one who died early from hepatic veno-occlusive disease (VOD). Five cases who were transplanted at the time of CR2 or CR3 and in advanced phase of lymphoma, relapsed 4 to 7 months after transplantation. The relapse rate was 31.3%. None of eight patients who received allogeneic BMT within 2 h after ABMT relapsed with median follow-up of 12 months and two of them died from procedure-related complications. Seven cases are still alive and disease-free with a median follow-up of 12 months. Mixed chimerism was found in 3/6 cases, who had different sex donors, by analysis of sex chromosomes. These results show that mixed transplantation is a safe, effective and new approach to treating patients with malignant tumors. In order to detect the effects of GVL, studies are now in progress in our clinic.